It is believed that an Exhaust Gas Regulator (xe2x80x9cEGRxe2x80x9d) consists of, among other components, a valve which is inserted into an exhaust gas flow passage. The valve is believed to control the flow rate of exhaust gas through the passage.
An EGR is also believed to comprise an actuator shaft that is connected to and manipulates the valve, and a motor that drives the actuator shaft. It is believed that the position of the valve within the exhaust gas flow passage subjects the valve to very high temperatures. It is further believed that the actuator shaft conducts heat energy from the valve to the motor, thereby increasing the operational temperature of the motor. It is yet further believed this temperature increase can adversely affect the motor""s performance and possibly damage the motor.
The present invention provides a valve including a wall, a closure member, a motive force device, and a coupling member. The wall defines a flow passage that is disposed along a longitudinal axis. The closure member is disposed in the flow passage and is rotatable on a first axis that is oblique to the longitudinal axis. The closure member is rotatable between a first position that substantially prevents flow through the flow passage and a second position that generally permits flow through the flow passage. The motive force device rotates the closure member between the first position and the second position. The device includes a rotor that is rotatably supported by a bearing, a stator that is proximate to the rotor, and an overmolded housing that positions the stator with respect to the bearing. The coupling member conveys motive force from the device to rotation of the closure member.
The present invention also provides a method of fabricating a valve. The valve includes a wall that defines a flow passage, a closure member that is disposed in the flow passage, and a motive force device that rotates the closure member with respect to the wall. The method includes overmolding a housing around a plurality of stationary components of the motive force device, inserting through an opening in the housing at least one rotating component of the motive force device, and occluding the opening with a housing cap